Spatially explicit methodology for coordinated manure management in shared watersheds

Abstract

Increased clustering and consolidation of livestock production systems has been linked to adverse impacts on water quality. This study presents a methodology to optimize manure management within a hydrologic region to minimize agricultural phosphorus (P) loss associated with winter manure application. Spatial and non-spatial data representing livestock, crop, soil, terrain and hydrography were compiled to determine manure P production rates, crop P uptake, existing manure storage capabilities, and transportation distances. Field slope, hydrologic soil group (HSG), and proximity to waterbodies were used to classify crop fields according to their runoff risk for winter-applied manure. We use these data to construct a comprehensive optimization model that identifies optimal location, size, and transportation strategy to achieve environmental and economic goals. The environmental goal was the minimization of daily hauling of manure to environmentally sensitive crop fields, i.e., those classified as high P-loss fields, whereas the economic goal was the minimization of the transportation costs across the entire study area. A case study encompassing two contiguous 10-digit hydrologic unit subwatersheds (HUC-10) in South Central Wisconsin, USA was developed to demonstrate the proposed methodology. Additionally, scenarios representing different management decisions (storage facility maximum volume, and project capital) and production conditions (increased milk production and 20-year future projection) were analyzed to determine their impact on optimal decisions.

The state of phosphorus balance on 58 Virginia dairy farms

“…Dairy manure as a liquid slurry is particularly difficult to export due to the transportation expense associated with the high water content (Kleinman et al., 2012). Likewise, in an area with a high density of dairy farms such as the Shenandoah Valley of Virginia, the supply of manure may exceed the demand, requiring creative logistics for exporting (Sharara et al., 2017).…”

Invited review: Sustainable forage and grain crop production for the US dairy industry

“…Substantial environmental advantages will accrue from reintegrating the feed and livestock operations, either on a given operation or among separate, nearby operations. With new tools, manure management may be coordinated, at least at the watershed level, to achieve appropriate loading rates and minimize economic costs and environmental impacts (Sharara et al, 2017).…”

Management of legacy nutrient stores through nitrogen and phosphorus fertilization, catch crops, and gypsum treatment

“…First, and most importantly, large nutrient legacy stores are often in areas with high livestock density, and the spatial differentiation of crop and livestock production is often the underlying cause of the high nutrient legacies (Svanbäck et al, 2019). We could extend the model to include manure as an input, but then we should also consider a spatial dimension, because in such a case transport costs become essential future of the problem (Lötjönen et al, 2020; Sharara et al, 2017). Second, we ignored the impacts of climate change, which may have significant influence on agricultural productivity and the externalities on the long run (Gornall et al, 2010).…”

“…Annual P load, is an increasing function of both and , because consists of two forms: the leaching of dissolved reactive phosphorus (DRP) and the loss of particulate phosphorus (PP). DRP is mostly determined by (McDowell & Sharpley, 2001; Peltovuori, 1999; Schnitkey & Miranda, 1993; Sharara et al, 2017). Annual N load, is also an increasing function of both and (Van Meter et al, 1998; Van Meter et al, 2018).…”